Archaea in Black Sea water column particulate matter and sediments—evidence from ether lipid derivatives

Phytane and long-chain, C40, head-to-head acyclic (C40:0cy) and cyclic isoprenoids with 1–3 cyclopentyl rings (C40:1cy, C40:2cy, and C40:3cy) derived from archaeal core lipids are present in Black Sea particulate matter from both the oxic and anoxic zones and in sediment cores from the central basin and the western continental margin. The occurrence of these ether-linked isoprenoids throughout the water column and sediments suggests that Archaea are widely distributed in the Black Sea. Methanogens are the probable source of ether-linked phytane and some of the acyclic C40 compounds while psychrophilic archaea related to hyperthermophiles are the likely sources of the cyclic isoprenoids.